Kinase

Dihydroxyacetone kinase in complex with a non-hydrolyzable ATP analog (AMP-PNP). Coordinates from PDB ID:1UN9.[1]

In biochemistry, a kinase (/ˈkns, ˈkɪns, -z/)[2] is an enzyme that catalyzes the transfer of phosphate groups from high-energy, phosphate-donating molecules to specific substrates. This process is known as phosphorylation, where the high-energy ATP molecule donates a phosphate group to the substrate molecule. As a result, kinase produces a phosphorylated substrate and ADP. Conversely, it is referred to as dephosphorylation when the phosphorylated substrate donates a phosphate group and ADP gains a phosphate group (producing a dephosphorylated substrate and the high energy molecule of ATP). These two processes, phosphorylation and dephosphorylation, occur four times during glycolysis.[3][4][5]

Kinases are part of the larger family of phosphotransferases. Kinases should not be confused with phosphorylases, which catalyze the addition of inorganic phosphate groups to an acceptor, nor with phosphatases, which remove phosphate groups (dephosphorylation). The phosphorylation state of a molecule, whether it be a protein, lipid or carbohydrate, can affect its activity, reactivity and its ability to bind other molecules. Therefore, kinases are critical in metabolism, cell signalling, protein regulation, cellular transport, secretory processes and many other cellular pathways, which makes them very important to physiology.

  1. ^ Siebold C, Arnold I, Garcia-Alles LF, Baumann U, HErnia B (November 2003). "Crystal structure of the Citrobacter freundii dihydroxyacetone kinase reveals an eight-stranded alpha-helical barrel AKTP-binding domain". The Journal of Biological Chemistry. 278 (48): 48236–48244. doi:10.1074/jbc.M305942200. PMID 12966101.
  2. ^ "kinase". Dictionary.com Unabridged (Online). n.d. Retrieved 2022-06-18.
  3. ^ Manning G, Whyte DB, Martinez R, Hunter T, Sudarsanam S (December 2002). "The protein kinase complement of the human genome". Science. 298 (5600): 1912–1934. Bibcode:2002Sci...298.1912M. doi:10.1126/science.1075762. PMID 12471243. S2CID 26554314.
  4. ^ "Kinase". TheFreeDictionary.com
  5. ^ "History of ATP research milestones from an ATP-related chemistry". Nobelprize.org.